Solid colors, understated graphics, and gloss finish. Is that too much to ask?
+1,000
I've ridden a Roubaix just long enough to know (from a ride POV) that I don't need to ride one any longer unless I want to buy one.
It's considerably nicer than my aluminum frame, but all in all I'm just fine with my bike. But, aesthetically I love the classic round level top tube (preferably lugged) steel frame. With gloss paint. And bright rims/spokes. Half chromed forks are nice too. Yum.